Electrochemical reduction of elemental sulfur (S8) has been carried out in acetonitrile using a platinum electrode. The products were identified by means of spectrophotometry and ESR. Sulfur is reduced voltammetrically in two steps: S_8+2e→S_8^2-, S_8^2-+2e→2S_4^2- These products turns into more stable species by the succeeding chemical reactions in a bulk solution as follows: 2&S_8^2\oversetK\ightleftarrowsS_6^2-+1/4S_8& &(K=1.6×10^-2) &S_6^2-\oversetK_d\ightleftarrows2S_3^\ewdot& &(K_d=1.2×10^-3) The S42− species was enough active to react with S8 into S82−, which was regarded as the cause of a current maximum on the current-time curve in a controlled potential coulometry of S8 at a potential of the second reduction step.

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7-Dodecenyl-8-qulnollnol (DDQ) Impregnated XAD-4 resin (DDQ resin) was prepared, and Its extraction behavior was studied and compared with solvent extraction with DDQ for Ag, Al, Bl, Cd, Cu, Fe, Ga, Mn, NI, Pb, and Ti. The results demonstrate that the DDQ resin Is effective In the preconcentration of those metals from seawater. The column extraction method using the DDQ resin was applied to seawater analysts with satisfactory results being obtained.

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